Our global life sciences company brings diagnostic testing & drug development together.

Fluorescence in situ Hybridization (FISH), Paraffin Block

CPT: Contact CPT coding department at 800-222-7566, ext 6-8400.
Print Share


  • Cytogenetics Fluorescence in situ Hybridization on Paraffin-embedded Tissue

Special Instructions

This test number is used for tracking FISH paraffin samples to the testing facility. Billing will occur after testing is completed.

Pertinent medical findings and probe desired must accompany request for FISH. If prior chromosome analysis has been performed, include a copy of the report. Please direct questions to genetics customer service at 800-345-4363.

Expected Turnaround Time

4 - 6 days

Related Documents

Specimen Requirements


Formalin/bone marrow-fixed (not decalcified); paraffin-embedded tissue or six 4-micron to 5-micron thick section slides


One paraffin block or six 4-micron to 5-micron thick section slides

Minimum Volume

Partial paraffin block to make several slides/probe


Paraffin block transport pouch


Specimen should be fixed in 10% neutral-buffered formalin or formaldehyde.

Storage Instructions

Maintain specimen at room temperature.

Causes for Rejection

Improperly embedded prep; poor fixation <6 hours and >72 hours; decalcified bone or bone core; broken or dirty slides; absence of tumor or quantity not sufficient for analysis

Test Details


For specific FISH probe analysis of tissue specimens


Samples in formaldehyde greater than 12 hours may reduce hybridization efficiency.

This test was developed, and its performance characteristics determined, by LabCorp. It has not been cleared or approved by the US Food and Drug Administration (FDA). The FDA has determined that such clearance or approval is not necessary.


Fluorescence in situ hybridization (FISH) from formalin-fixed tissue-embedded paraffin (4-micron to 5-micron sections); H&E for pathology review.


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
510825 FISH Paraffin Block Test 510826 Specimen Type 31208-2
510825 FISH Paraffin Block Test 510827 Cells Counted 62361-1
510825 FISH Paraffin Block Test 510828 Cells Analyzed 62360-3
510825 FISH Paraffin Block Test 510829 FISH Result 59267-5
510825 FISH Paraffin Block Test 510831 Interpretation 50398-7
510825 FISH Paraffin Block Test 510832 Director Review: 48672-0
510825 FISH Paraffin Block Test 512123 PDF 51967-8

For Providers

Please login to order a test

Order a Test

© 2021 Laboratory Corporation of America® Holdings and Lexi-Comp Inc. All Rights Reserved.

CPT Statement/Profile Statement

The LOINC® codes are copyright © 1994-2021, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee. Permission is granted in perpetuity, without payment of license fees or royalties, to use, copy, or distribute the LOINC® codes for any commercial or non-commercial purpose, subject to the terms under the license agreement found at Additional information regarding LOINC® codes can be found at, including the LOINC Manual, which can be downloaded at